South Africa's City Press, in an exclusive entitled 'The Case Against Oscar', reported that the bat may have either been used by Pistorius to break down the door of the bathroom where her body lay, or it was used by the law graduate to defend herself.

The paper said one bullet cartridge was found in Pistorius' bedroom, and police are investigating whether the first shot was fired in the bedroom, before bullets were fired through the door of the bathroom.

Steenkamp was shot in the early hours in Pistorius' home on Thursday

Pistorius sobbed uncontrollably during a court appearance on Friday during which he was formally charged with murder.

Divaris added: "I said to him, 'What are you talking about? I don't understand you?' He then repeated himself - 'There has been a terrible accident, I shot Reeva'."

The arrest of Pistorius, who won two gold medals and a silver at the 2012 Paralympic Games in London, triggered shock across the globe and prompted rumours that he may have mistaken his girlfriend for an intruder in what could have been a Valentine's Day surprise gone wrong.

But police swiftly distanced themselves from that suggestion and said there had been previous incidents of a "domestic nature" at the gated property.

His family has already issued a statement in which they vowed to fight the murder charge in the "strongest terms".

Arnold Pistorius, the athlete's uncle, reiterated this on Saturday, saying: "After consulting with legal representatives we deeply regret the allegation of premeditated murder.

"We have no doubt there is no substance to the allegation and that the state's own case, including its own forensic evidence, strongly refutes any possibility of a premeditated murder or indeed any murder at all."

Pistorius will appear in court on Tuesday for a bail hearing, something police have said they oppose. Prosecutors also say they will pursue upgraded charges of premeditated murder against him, which means the athletics hero could face a life sentence.